Current design processes, using “build and test” prototype engineering, will not suffice. Concurrently, fuels will also be evolving, adding another layer of complexity and further highlighting the need for efficient product development cycles. Achieving these goals will require the transportation sector to compress its product development cycle for cleaner, more efficient engine technologies by 50% while simultaneously exploring innovative design space. Achievable advances in engine technology can improve the fuel economy of automobiles by over 50% and trucks by over 30%. Because of their relatively low cost, high performance, and ability to utilize renewable fuels, internal combustion engines-including those in hybrid vehicles-will continue to be critical to our transportation infrastructure for decades. Increasing the efficiency of internal combustion engines is a technologically proven and cost-effective approach to dramatically improving the fuel economy of the nation’s fleet of vehicles in the near- to mid-term, with the corresponding benefits of reducing our dependence on foreign oil and reducing carbon emissions. At the same time, transportation produces one-quarter of the nation’s carbon dioxide output. Because the transportation sector accounts more » for two-thirds of our petroleum use, energy security is deeply entangled with our transportation needs. spends $1 billion per day on imported oil to meet our energy demands. Oil prices remain volatile and have exceeded $100 per barrel twice in five years. has reached a pivotal moment when pressures of energy security, climate change, and economic competitiveness converge. This report is based on a SC/EERE Workshop to Identify Research Needs and Impacts in Predictive Simulation for Internal Combustion Engines (PreSICE), held March 3, 2011, to determine strategic focus areas that will accelerate innovation in engine design to meet national goals in transportation efficiency. Finally, to simplify the requirements for the roton tip seals and to enhance the introduction and combustion of fuel, a flush-mount fuel injector was designed, manufactured and demonstrated in the GEN2.5B prototype. The design enhancements developed with the test fixture were also incorporated into the GEN2.5B prototype and tested and evaluated using the iterative research strategy described below. Enhancement of the housing side seal system was accomplished using a custom designed side seal test fixture. As the roton tip seal performance was improved, results pointed toward inadequate performance of the housing side seals. The variation in more » compression pressures was characterized versus design features. Compression pressures adequate for compression ignition of diesel fuel were achieved, although not consistently in all combustion volumes. Enhancements to the tip seal design were incorporated into the GEN2.5B prototype and tested and evaluated using the iterative research strategy described below. The Decision Point at the end of Phase 1 of the project (described below) was to further optimize the existing tip seal design. This design was incorporated into the GEN2.5A prototype and tested for achievable compression pressure. The design was evaluated using a custom designed and fabricated seal test fixture and further refined.
The PST concept for the roton tip seal was developed into a manufacturable design. The key technical challenge to the Legacy engine's commercialization, and the focus of this project, was the development of a viable roton tip seal. These advances are achieved through a combination of innovative design geometry, rotary motion, aspiration simplicity, and manufacturing/part simplicity. The Legacy engine offers significant advances over conventional internal combustion engines in 1) power to weight ratio 2) multiple fuel acceptance 3) fuel economy and 4) environmental compliance. The Legacy engine is a completely new design, transitional diesel engine, replacing the reciprocating engine with a rotary engine.